Turbocharger assembly and method

ABSTRACT

A turbine assembly is provided. The turbine assembly includes a turbocharger drive having a first threaded portion and a turbine wheel assembly. The turbine wheel assembly includes a turbine wheel and a second threaded portion adapted to engage the first threaded portion of the turbocharger drive. The turbine assembly may be utilized in a turbocharger assembly, wherein a compressor is connected to a second end of the turbocharger drive.

U.S. GOVERNMENT RIGHTS

This invention was made with government support under the terms ofContract No. DE-SC05-00OR-22810 awarded by the Department of Energy. Thegovernment may have certain rights in this invention.

TECHNICAL FIELD

The present invention is directed to a turbocharger assembly and, moreparticularly, to a turbocharger assembly that provides for removablyconnecting a turbine wheel assembly to a turbocharger drive.

BACKGROUND

Internal combustion engines such as, for example, diesel engines,gasoline engines, or natural gas engines may be operated to generate apower output. In order to maximize the power generated by the internalcombustion engine, the engine may be equipped with a turbocharged airinduction system.

A turbocharged air induction system may include a turbocharger thatcompresses the air flowing into the engine to thereby force more airinto a combustion chamber. The increased supply of air allows forincreased fuelling, which may result in increased power. A turbochargedengine typically produces more power than the same engine withoutturbocharging.

A turbocharger may include a turbine wheel that is connected to acompressor. The expansion of hot exhaust gases over the turbine wheeldrives the compressor wheel to force compressed air into a combustionchamber. A typical turbocharger includes a housing, a shaft, a turbinewheel attached to one end of the shaft, and a compressor connected bythreaded fastening to the other end of the shaft. The turbine, shaft,and compressor may be assembled into the housing as described in U.S.Pat. No. 5,193,989 issued to Fleury et al. on Mar. 16, 1993. The '989patent to Fleury et al. describes assembly of a turbocharger having theturbine wheel permanently attached to the shaft. The shaft and turbinewheel may be inserted from one side of the housing and the compressorwheel may be fastened to the other end of the shaft.

However, the turbocharger of Fleury et al. does not allow for the designflexibility required for more complex turbocharging systems that requireadditional components. Adding the additional components to theturbocharger systems of Fluery et al. may be difficult because theturbocharger components may only be assembled from one end of theturbocharger shaft. Additionally, the turbocharger of Fleury et al. maybe too expensive to maintain when combined with more complex airinduction systems because the turbine wheel and shaft are inseparable.

The turbocharger assembly of the present invention solves one or more ofthe problems set forth above.

SUMMARY OF THE INVENTION

A first aspect of the present disclosure is directed to a turbineassembly. The turbine assembly includes a turbocharger drive having afirst threaded portion and a turbine wheel assembly. The turbine wheelassembly includes a turbine wheel and a second threaded portion adaptedto engage the first threaded portion of the turbocharger drive.

A second aspect of the present disclosure is directed to a method ofassembling a turbocharger. The method includes inserting a drive into amain housing, wherein the turbocharger drive includes a first end havinga first threaded portion and a second end. A second threaded portion ofa turbine wheel assembly is engaged with the first threaded portion ofthe turbocharger drive. A compressor is connected to the second end ofthe turbocharger drive.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional illustration of a turbine assembly inaccordance with an exemplary embodiment of the present invention.

FIG. 2 is a cross-sectional illustration of a turbine assembly inaccordance with an exemplary embodiment of the present invention.

FIG. 3 is a cross-sectional illustration of a turbocharger in accordancewith an exemplary embodiment of the present invention.

FIG. 4 is a diagrammatic and schematic illustration of an engine systemin accordance with an exemplary embodiment of the present invention.

DETAILED DESCRIPTION

An exemplary embodiment of a turbine wheel assembly 10 is illustrated inFIG. 1. The turbine wheel assembly 10 includes a turbine wheel 11 havinga turbine wheel base 12 and a plurality of turbine blades 13. Theplurality of turbine blades 13 may be disposed on the outer periphery ofthe turbine wheel base 12 and may be adapted to rotate the turbine wheelbase 12 when driven by the expansion of hot exhaust gases. The pluralityof turbine blades 13 may be rigidly fixed to the turbine wheel base 12using conventional means or they may be movable with respect to theturbine wheel base 12 such as, for example, by providing variable pitchturbine blades or variable geometry turbine blades. The plurality ofturbine blades 13 may also be integral with the turbine wheel base 12.

The turbine wheel assembly 10 may also include a connecting means suchas for example, a threaded portion 14. The threaded portion 14 may beintegral to turbine wheel base 12 or may be connected to the basethrough any means known in the art such as, for example, inertiawelding. The threaded portion 14 may be adapted to transmit power fromthe turbine wheel assembly 10 to a corresponding connecting member.

In the embodiment of FIG. 1, the threaded portion 14 of the turbinewheel assembly 10 is adapted to engage a corresponding connecting meansof a turbocharger drive 18. In this embodiment, the connecting means isa threaded portion 16. When the threaded portion 14 of the turbine wheelassembly 10 is engaged with the threaded portion 16 of the turbochargerdrive 18, the turbine wheel assembly 10 is connected to the turbochargerdrive 18 so that a rotation of the turbine wheel assembly 10 will causea corresponding rotation of the turbocharger drive 18.

In the exemplary embodiment of FIG. 1, the threaded portion 14 ofturbine wheel assembly 10 has male threads and the threaded portion 16of the turbocharger drive 18 has female threads. The male threads of theturbine wheel assembly 10 may be engaged with the female threads toconnect the turbine wheel assembly 10 to the turbocharger drive 18. Theturbine wheel assembly 10 may alternatively have a female threadedportion adapted to engage a male threaded portion of the turbochargerdrive 18.

Another exemplary embodiment of a turbine wheel assembly 10 isillustrated in FIG. 2. The turbine wheel assembly 10 of this embodimentincludes a turbine wheel 11 and a stub shaft 20 having a threadedportion 22. The stub shaft 20 may be integral to turbine wheel base 12or may be connected to turbine wheel base 12 by any manner known in theart such as, for example, inertia welding. The stub shaft 20 may includea female threaded portion 22 adapted to engage a male threaded portion16 located on the turbocharger drive 18 (referring to FIG. 1), therebyconnecting the turbine wheel assembly 10 to the turbocharger drive 18.Alternatively, the stub shaft 20 may include a male threaded portionadapted to engage a female threaded portion located on the turbochargerdrive 18.

It is contemplated that the turbine wheel assembly 10 may beincorporated in a turbocharger assembly. An exemplary embodiment of aturbocharger 23 is illustrated in FIG. 3. In this embodiment, theturbocharger 23 includes a stator housing 24 in which a pre-assembleddrive assembly 26 may be inserted.

The pre-assembled drive assembly 26 may have a stator 28 and a rotor 29held by end plate retainers 34 between bearings 30. The stator 28, rotor29, end plate retainers 34, and bearings 30 are assembled to theturbocharger drive 18. The pre-assembled drive assembly 26 may beadapted to generate power when the turbocharger drive 18 is rotated anddirect the power to a crankshaft of an engine 46 (referring to FIG. 4)to which the turbocharger 23 is attached.

A turbine housing 40 is assembled to stator housing 24 to encloseturbine wheel assembly 10. The turbine housing 40 is adapted to directhot expanding exhaust gases through a turbine exhaust inlet 41 to theplurality of turbine blades 13 disposed on the turbine wheel base 12 tocause the turbine wheel assembly 10 and associated turbocharger drive 18to rotate. After passing through the turbine wheel assembly 10, theexhaust gases are released to the atmosphere through a turbine exhaustoutlet 42.

A compressor assembly 37 may be connected to the other end of theturbocharger drive 18 and be adapted to rotate with the turbochargerdrive 18. The compressor assembly 37 may include a compressor wheel base38 and a plurality of compressor blades 39 disposed around the outerperiphery of the compressor wheel base 38. Compressor assembly 37 mayalso include a stub shaft (not shown) having a fastening means such asfor example, threads, similar to stub shaft 20 connected to turbinewheel 11. The stub shaft of compressor assembly 37 may be adapted toconnect the compressor assembly 37 to the turbocharger drive 18.

A compressor housing 43 may be assembled to the stator housing 24 thatencloses compressor assembly 37. Compressor housing 43 is adapted todirect ambient air from a compressor air inlet 44 to the plurality ofcompressor blades 39 attached to the rotating compressor wheel base 38.The plurality of compressor blades 39 may be operable to compress theair and force the compressed air out of the turbocharger 23 through acompressor air outlet 45 (referring to FIG. 4).

As illustrated in FIG. 4, the turbocharger 23 of the present disclosuremay be used with an engine 46 in an engine assembly 48. The engine 46may be a diesel engine, a gasoline engine, a natural gas engine, or anyother engine known in the art. Hot exhaust gases from the engine 46 aredirected into the turbine exhaust inlet 41 where the gases drive therotation of the turbine assembly 10 resulting in a correspondingrotation of compressor assembly 37. The rotation of compressor assembly37 compresses inlet air and forces the compressed air into the engine 46through compressor air outlet 45.

Industrial Applicability

As will be apparent from the foregoing description, the presentdisclosure provides a system and method that allows for designflexibility and low cost maintenance of a turbocharger 23.

The turbocharger 23 of the present disclosure may be assembled from bothends of the turbocharger drive 18. The pre-assembled drive assembly 26(having stator 28, rotor 29, end plate retainers 34, bearings 30, andturbocharger drive 18) is balanced and then inserted into stator housing24. Turbine wheel assembly 10 is connected to one end of theturbocharger drive 18 by engaging threaded portion 14 of the turbinewheel assembly 10 with threaded portion 16 of the turbocharger drive 18.Turbine housing 40 is assembled to one side of the stator housing 24 andencloses the turbine wheel assembly 10. Compressor assembly 37 may beconnected to the other end of the turbocharger drive 18 and enclosed bycompressor housing 43 assembled to the other side of the stator housing24.

Because the turbocharger 23 can be assembled from both sides of theturbocharger drive 18, design flexibility is expanded. Design is nolonger limited to components capable of assembly from only onedirection. Likewise, methods of assembly are no longer limited to onlyone direction of assembly.

In addition to increased design flexibility, maintenance costs of theturbocharger 23 may be reduced by the ability to remove both the turbinewheel assembly 10 and the compressor assembly 37 from the turbochargerdrive 18. For example, when maintaining a turbocharger having a turbinewheel permanently secured to a turbocharger drive, replacement of adamaged turbine wheel required the entire turbocharger be taken apart.Both turbine and compressor housings had to be removed and thecompressor assembly had to be disconnected from the turbocharger drive.The pre-assembled drive assembly had to be removed from the statorhousing along with the turbine wheel and the turbocharger drive. Thepre-assembled drive assembly had to be separated from the turbochargerdrive. Finally the turbine wheel and turbocharger drive could bereplaced.

With the turbine wheel assembly 10 detachable from the turbochargerdrive 18 as described in the present disclosure, the maintenance processis simplified. For example, when replacing a broken or damaged turbinewheel assembly 10, the turbine housing 40 is removed and the turbinewheel assembly 10 is detached. Not only is the process simplified savingtime and labor cost, but part cost is also reduced.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the turbine wheel assembly10 of the present disclosure without departing from the scope of theinvention. Other embodiments of the invention will be apparent to thoseskilled in the art from consideration of the specification and practiceof the invention disclosed herein. It is intended that the specificationand examples be considered as exemplary only, with a true scope of theinvention being indicated by the following claims and their equivalents.

1. A turbine assembly, comprising: a turbocharger drive having a firstthreaded portion; and a turbine wheel assembly having a turbine wheeland a second threaded portion adapted to engage the first threadedportion of the turbocharger drive.
 2. The turbine assembly of claim 1,wherein the turbine wheel assembly includes a turbine shaft having afirst end and a second end, the first end of the turbine shaft havingthe second threaded portion and the second end of the turbine shaftbeing connected to the turbine wheel.
 3. The turbine assembly of claim1, wherein the second threaded portion of the turbine wheel assembly hasmale threads.
 4. The turbine assembly of claim 1, wherein the secondthreaded portion of the turbine wheel assembly has female threads. 5.The turbine assembly of claim 1, further including a turbine housingenclosing the turbine wheel assembly.
 6. The turbine assembly of claim5, further including at least one bearing operatively connecting theturbocharger drive to the housing.
 7. The turbine assembly of claim 2,wherein the second end of the turbine shaft is inertia welded to theturbine wheel.
 8. The turbine assembly of claim 1, further including: aturbine wheel base; and a plurality of turbine blades disposed aroundthe outer periphery of the turbine wheel base.
 9. A method of assemblinga turbocharger comprising: inserting a turbocharger drive into a mainhousing, wherein the turbocharger drive includes a first end having afirst threaded portion and a second end; engaging a second threadedportion of a turbine wheel assembly with the first threaded portion ofthe turbocharger drive; and connecting a compressor to the second end ofthe turbocharger drive.
 10. The method of claim 9, further including:pre-assembling the turbocharger drive before inserting the turbochargerdrive into the main housing, wherein pre-assembling the turbochargerdrive includes: installing a shaft through a rotor; and balancing therotor.
 11. The method of claim 9, further including: attaching a turbinehousing to the main housing thereby enclosing the turbine wheelassembly; and attaching a compressor housing to the main housing therebyenclosing the compressor.
 12. A turbocharger, comprising: a housingassembly; a turbocharger drive rotatingly disposed in the housingassembly, the turbocharger drive including a first end having a firstthreaded portion and a second end; a turbine wheel assembly having aturbine wheel and a second threaded portion adapted to engage the firstthreaded portion on the turbocharger drive; and a compressor connectedto the second end of the turbocharger drive.
 13. The turbocharger ofclaim 12, wherein the turbine wheel assembly includes a shaft having afirst end and a second end, the first end of the shaft having the secondthreaded portion and the second end of the shaft being connected to theturbine wheel.
 14. The turbocharger of claim 12, wherein the secondthreaded portion of the turbine wheel assembly has male threads.
 15. Theturbocharger of claim 12, wherein the second threaded portion of theturbine wheel assembly has female threads.
 16. The turbocharger of claim12, wherein the compressor includes a third threaded portion adapted toengage a fourth threaded portion disposed on the second end of theturbocharger drive.
 17. The turbocharger of claim 13, wherein thecompressor includes a shaft having a first end and a second end, thefirst end of the shaft having the third threaded portion and the secondend connected to the compressor.
 18. The turbocharger of claim 12,wherein the housing assembly includes: a main housing enclosing theturbocharger drive; a compressor housing enclosing the compressor; and aturbine housing enclosing the turbine assembly.
 19. The turbocharger ofclaim 12, wherein the turbocharger drive includes: a shaft; and a rotoroperably connected to the shaft.
 20. A turbocharger, comprising: ahousing assembly; a turbocharger drive rotatingly disposed in thehousing assembly; a turbine wheel assembly having a turbine wheel and ameans for removably connecting the turbine wheel to the turbochargerdrive; and a compressor connected to the second end.
 21. Theturbocharger of claim 20, wherein the turbine wheel assembly includes ashaft having a first end and a second end, the first end of the shafthaving the connecting means and the second end of the shaft beingconnected to the turbine wheel.